SAN Client Cluster Name using LAN to backup

My Environment :

Master Server
Windows 2012
NetBackup Master 7.6.0.1

Media Server
NetBackup Appliance 5230 
NetBackup 2.6.1

Client
AIX 6.1 TL8
NetBackup client 7.6.0.1

I just install 2 x client and enable SAN as transport.

i create policy and test with individual client, all goes well, transport type : FT

But, when i try to use the cluster name to do backup, it use LAN. i double check that the nbemmcmd, my cluster name only show as app_cluster and no client entry, i not sure what have i miss during the configuration or this is a bug for this version.